Vacuum-tube lamp.



N0. 853,989. PATENTED MAY 21, 1907. D. MOP. MOORE.

VAGUUM TUBE LAMP. APPLIOATION FILED APR.21.1904.

WITNESSES: 'INVENTOH ATTORNEY-5 UNITED 's'rA rns ENT OFFICE.

DANIEL MoFARLAN MOORE, OF" NEWARK, NEW JERSEY, ASSIGNOR TO MOORE ELECTRICAL COMPANY, OF NEW YORK, N. Y., A CORPORA- TION OF NEW YORK.

VACUUM-TUBE LAMP.

' Specification of L tters Patent.

Patented May 21, 1907.

Application filed April 21, 1904. Serial No. 204,175.

- kind, said gas or vapor being ordinarily somewhat rarefied and inclosed in a suitable transparent receiver, tube or bulb.

The main object of my invention is to produce a light of this character which shall give sufficient red rays to give a red light, or which, in those cases where the red rays are deficient, shall supply the red rays to correct the colorof the light, as for instance, inthe case of mercury vapor lamps wherein the absence of the red rays gives the Well-known peculiar green or violet color.

A furtherobject of my invention is to secure stability in the degree of rarefaction of the contained gas or vapor, in which respects my invention is especially useful for that class of lamps in which the luminous source is a somewhat highly rarefied gas stable at the usual temperatures of the atmosphere.

My invention consists in the provision of a peculiar material which is introduced into the lamp in any desired way and as to one of the materials which I propose to employ, my invention is an improvement upon my prior application filed September 2nd, 1903, Serial No. 171,587, while as to another, namely, the material hereinafter denominated aubepine, my present invention is a continuation of that application wherein I have described the use of an electrolytically treated aubopine, or a benzamid for improving the color, efficiency and life of the lamp and, in the case of mercury or vapor lamps, for'supplying the missing red rays.

My invention so far as concerns the mercury vapor lamp, or other lamp in which the illuminating agent is a vapor of a metal, consists in the application to'the interior of such lamp'of some electrolytically treated organic substance, preferably one of which nitrogen is a constituent, said material being, howapplied. The tube ever, in the case of a mercury or other lamp, preferabl electrol tically treated hydro- )enzami or the al ehyde of anise known as aubepine, or some other electrolytically. treated benzamid or a benzamid produced by electrolytic treatment of an organic substance.

The required material may be produced by the subjecting of the organic substance to electrolytic action either with or without the presence of nitrogen. ganic compound, animal or vegetable for the electrolytic treatment, but preferably an aromatic hydrocarbon such as benzine, tolu-- one, 620., or a derivative thereof such as anislc, bcnzoic (without nitrogen) hlppuric acid and benzamid (with nitrogen). This treatment can be conveniently carried on in a short tube of glass provided with energy transferring electrodes by which an alternating or other current may be passed through the contents of the tube. Said electrodes may be external caps or pieces of metal which transfer energy by electrostatic action, or may be internal electrodes. Ordinarily, and particularly Where the material is to be used to supply the red rays, I em loy as the material to be treated, the aldehy e of anise known as aubepine.

For the purpose of facilitating the production of the material as well as securing the red rays, I employ as the substance electrolytically treated an hydramid of anise which may be produced by mixing aubepine and ammonia as a liquid mixture, which is then slowly evaporated to produce a stiff dough that is afterward ground up into an impalpab'le'powder. The material produced by electrolytic treatment of this substance has the further advantage that a gas lamp containing such material is highl efficient. I The material to be treatecf may be introduced, if it be a solid, into the tube in pow- I employ in the or-- dered form and distributed by rotating the tube, heat being applied externally when necessary to cause it toadhere to the Walls of the tube. In some cases where the substance to be treated will sublime Without decomposition (anisic or benzoic acid) I prefer to place the tube in a slanting position with the substance occupying the lower end, or in a suitable tubular progection, to which heat is lls with vapor, which the tube with a thin film by rotating in a horizontal position.

The substance is subjected to an electrolytic action in any desired way, but it is preferable to carry on the process while the substance is inclosed in a receiver from which theair or other gas used in the treatment may.

be exhausted to a greater or less degree to hasten the process. For this purpose the tube above mentioned may be sealed up and attached to a vacuum pump which is oper-' ated to exhaust the gas or reduce the same to a more tenuous condition while at the same time electric currentis passed throughthe tube in any suitable manner aided in some cases by heat, if necessary, to assist the decomposition of the substance. In this oper ation the decomposing effect of the current is accompanied by a change in the color of the gaseous contents of the tube from a red color at the beginning of the operation to a thick white as the exhaustion progresses. This change takes place when the action progresses in the normal and expeditious manner, but when, for instance, crystals of hippuric acid are employed it is found that even with the continued application of the current no apparent decomposing efl'ect takes place, and that the light in the tube instead of changing quickly from a red color at the beginning of the operation to a white as the exhaustion progresses, changes from a red to a very thin white. In this instance the action is assisted by the application of external heat. The resultant compound appears as a fixed solid residue more or less spongy but still firmly adherent coating upon the walls of the tube extending beyond the electric terminals. The composition of this coating is uncertain but in all preferred forms, benzamid, and in many cases acetamid is present in considerable quantity. In the case of benzoic or anisic acid, or other substances containing no nitrogen, and similar'hydrocarbons these amids are formed by the fixation of the nitrogen of the air in the tube while the current is traversing the tube. In this operation the production of the coating seems to be assisted by lowering the pressure of the air or other gas within the tube, although as hereinafter described, the same material may be obtained by treating the substance mentioned in the open air, but with less facility. The change of the color from a deep red to a pure white during the treatment probably marks the fixation of the nitrogen and the production of the amid or other organic compound having nitrogen for one of its constituents.

In place of carrying on the treatment of I the material in the presence of air rarefied more or less, I may employ pure nitrogen introduced into the tube and subsequently, if desired, partially exhausted. I may also apply the treatment to a substance embracing nitrogen as a constituent, for example, benzonitrll, 'benzamid, acetamid, &c. The material resulting may be introduced with benefit into a metal vapor lamp being, in the case of mercury, placed on the surface of the bodyl of mercury or otherwise applied.

T e presence of the material may be Se cured in the lamp by treating the substance before named electrolytically in the tube or receptacle of glass to be employed as the finished lamp or the coating in the tube in which it is formed may be removed and introduced I into another tube which is substantially exhausted, or it may be removed as a coating and placed on the body of mercury of a mercury vapor lamp or otherwise introduced into the same.

The material produced by the decomposition of an anise hydramid as described may be beneficially employedin any electrolytically-operated tubein which it is desired to maintain a suitable de ree of rarefaction. In a vacuum tube lamp it has the further advantage that a lower degree of vacuum maybe employed thus rendering it possible to employ mechanical exhaustion pumps in-- stead of the usual mercury pumps.

Instead of manufacturing the material in the sealed tube it may be prepared by spreading the organic substance on a plate of glass and then passing electrolizing current through it by placing one terminal of a high tension source of electricity above it and close to the film or layer or material. This causes high tension sparks to radiate all over and through the chemical causing art of it to evaporate and after some time saving a residue in the form of a coating on the plate that is similar to that produced within the tube which has ahighvacuum pump attached to it. However, I have found that this latter method is far more laborious, more expensive, and not nearly as preferable as the vacuum process. Instead of removing the material by scraping the material off the tube in which it is formed, it may be washed off by the use of various liquids and then recovered by evaporation.

In the accompanying drawings, Figure 1 shows the mercury vapor lamp containing the electrolytically produced material, preferably as already described, a benzamid or an electrolytically-treated aubepine or anise hydramid to secure the presence of the red rays the light; Fig. 2 shows the tube in which the material may be produced and substantially recovered by opening the tube; Fig. 3 shows one end of the tube provided with means for introducing the substances to be heated as a vapor. Fig.4 shows a modicury electrode at one end of the tube.

which the formation of the material maybe observed, and provided at its ends with conducting caps 3 to which are connected electrio conductors H for the supply of electric energy to be electrostatically transferred through said conducting caps to the contents of the tube. Said caps, 3, may be of plunibago, orother good conducting material. Attached to the larger receptacle is a small tube, 4, adapted for connection to an exhaust pump and designed to permit the sealing off .when the operation has been conducted to the desired point. In the case of Fig. 2, it is assumed that the substance is introduced as a liquid or else as a solid.

In Fig. 3, 6, indicates a receptacle in which the substance may be placed so that when heated its vapors will pass into the tube and condense on the walls thereof after which the electrical treatment of the substance may be carried on.

In Fig. 4-, 9, indicates a plate upon which the substance 10', to be treated, maybe spread, and 11 and 12the electrodes for electrolyzing said material in the manner previously mentioned, namely in the open air.

In Fig. 1-, the electrolytically treated material is shown at 7, on the surface of the me;-

.n practice, for a gas vapor lamp the resenee of from three to four drams of the e ectrolytically treated anise hydramid to one hundred feet of tubing, more or less, will be sufficient. Any aromatic hydro-carbon either in the liquid or powder form can be so placed. However, it is preferable to use a comparatively small quantity, compared with the amount of surface of the mercury of the white powder known as anise-hydramid. It

.w ill not interfere with the vaporization of the mercury, and in a short time it will coat the surface of the tube near and above the surface of the mercury. Another form of aromatic hydro-carbon for this p ose is the benzaldehyde, which in a tube without mercury gives a permanent red color. It is also a white powder which smells strongly of hydrocyanic acid, the odor of which is somewhat similar to that of peach kernels or bitter almond. Therefore it is particularly suitable for supplying the red rays on the mercury tube. Another form richin red rays is the hydro-benzamid. Besides these there are mercury compounds which are suitable for, in a measure at least, correcting the otherwise very poor spectrum of mercury. For example:mercuric-benzoate placed in a tube without any liquid mercury gives a spectrum much better than could be obtained by the pure mercury alone. Also mercuro-benzamid, which is a white powder, has been found to also be suitable for this purpose.

What I claim as my invention is:

1. An electric gas or vapor lamp containing an electrically treated hydro-benzamid.

2. A metal vapor electric lamp containing an electrolytically treated organic substance.

3. A metal vapor electric lamp containing material produced by electrolysis of an organic substance of which nitrogen is a constituent.

4. An electric-metal vapor lamp containing a material produced by electrolysis of a compound of hydrogen and carbon.

5. A mercury vapor electric lamp containing also an organic substance.

Signed at New York in the county of New York and State of New York this 4th day of March, A. D. 1904.

DANIEL MCFARLAN MOORE. 

